1. Field of The Invention
The present invention relates to the use of analogs of glutamic acid and gamma-aminobutyric acid (GABA) for the treatment of insomnia.
2. Description of Related Art
GABA analogs are known agents useful in antiseizure therapy for central nervous system disorders such as epilepsy, Huntington's chorea, cerebral ischemia, Parkinson's disease, tardive dyskinesia, and spasticity. It has also been suggested that the compounds can be used as antidepressants, anxiolytics, and antipsychotics. See WO 92/09560 (U.S. Ser. No. 618,692 filed Nov. 27, 1990) and WP 93/23383 (U.S. Ser. No. 886,080 filed May 20, 1992).
WO 97/33858 teaches that compounds related to gabapentin are useful or treating epilespy, faintness attacks, hypokinesia, cranial disorders, neurodegenerative disorders, depression, anxiety, panic, pain, and neuropathological disorders. WO 97/33858 does not specify what forms of pain are treated.
Additionally, the compounds of the invention are known for treatment of neuropathic pain. For example, see Rosner H; Rubin L; Kestenbaum A., Gabapentin adjunctive therapy in neuropathic pain states. Clin J Pain, 1996 March, 12:1, 56-8; Segal A Z; Rordorf G., Gabapentin as a novel treatment for postherpetic neuralgia. Neurology, 1996 April, 46:4, 1175-6; Wetzel C H; Connelly J F., Use of gabapentin in pain management. Ann Pharmacother, 1997 September 31:9, 1082-3; Zapp J J., Postpoliomyelitis pain treated with gabapentin [letter]. Am Fam Physician, 1996 June, 53:8, 2442, 2445; Cheville A, et al., Neuropathic pain in radiation myelopathy: a case report. Program book, American Pain Society (14th Annual Scientific Meeting). Abstract #95823, p. A-115; Sist T; Filadora V; Miner M; Lema M., Gabapentin for idiopathic trigeminal neuralgia: report of two cases. Neurology, 1997 May 48:5, 1467; Waldman S D, Tutorial 28: Evaluation and Treatment of Trigeminal Neuralgia. Pain Digest (1997) 7:21-24; Mellick L B; Mellick G A., Successful treatment of reflex sympathetic dystrophy with gabapentin [letter]. Am J Emerg Med, 1995 January, 13:1, 96; Mellick G A; Seng M I., The use of gabapentin in the treatment of reflex sympathetic dystrophy and a phobic disorder. Am J Pain Manage 1995; 5:7-9; Mellick G A; Mellicy L B; Mellick L B., Gabapentin in the management of reflex sympathetic dystrophy [letter]. J Pain Symptom Manage, 1995 May, 10:4, 265-6; Mellick G A; Mellick L B., Reflex sympathetic dystrophy treated with gabapentin. Arch Phys Med Rehabil, 1997 January, 78:1, 98-105 and Mackin G A., Medical and pharmacologic management of upper extremity neuropathic pain syndromes. J Hand Ther, 1997 April-June, 10:2, 96-109.
Insomnia and sleeplessness are common problems. Often, the insomnia or sleeplessness is precipitated by stress, emotional and physical causes.
U.S. Pat. No. 5,510,381, directed to the use of gabapentin to treat mania, mentions one study in which gabapentin has also been found to enhance delta-wave (deep) sleep. This effect is beneficial in acute mania and also leads to reducing the risk for onset of a new episode of mania.